Recently there has been an unprecedented surge of activity by lightning.This is due to the constant strengthening of electromagnetic smog, which is due to the widespread use of electronics and home appliances, means of communication and connection.Therefore, lightning protection of buildings and structures in our day has become particularly popular.
Since ancient times, the lightning was seen as something inevitable and irresistible, and from its destructive action, no one could be saved.The world first learned about the origin of the electrical lightning in 1753 thanks to the experience and the development of Franklin's lightning rod.The following ideas related to the improvement of systems of lightning prot
Lightning lamented different abilities, atmospheric discharge is considered particularly dangerous to human life and property.The growing need for the use of sensitive modern technology have led to the fact that the external environment has become extremely sensitive to the effects of different kinds of surge.
In the seventies of the last century, some foreign firms have begun to draft lightning and engaged in the production of active lightning.The first models were equipped with radioactive sources, as it was considered that due to the radiation of radioactive lightning rod capable of forming a channel of ionized air, which increases the height of the device and, therefore, its protection space.
categories under the terms of protection ↑
In our country developed and adopted classification of buildings and buildings under the terms of protection against the harmful effects of lightning, regardless of the level of risk of the discharge and the selection of appropriate measures of protection.
The first category rank buildings that contain unencrypted or processed or where explosives are stored for a long time or occur regularly mixture of gases, dust and vapors of flammable substances with air and other oxidizing agents that are able to explode by electric sparks.
The second group includes the building where flammable or explosive materials are firmly plugged and dangerous mixture of fumes, dust and gases with air occur exclusively during malfunctions or accidents.
All other facilities including farm buildings and houses, which are due to the lightning can suffer from mechanical damage or a fire, represent the third category.Lightning protection of buildings regulated by IEC 01/01/1024, which established four categories of lightning that have the following efficiency: I - 98%, II - 95%, III - 90%, IV - 80%.
rules and criteria for calculating ↑
Lightning Calculation is based on a quantitative assessment of the possibility of electric shock from the protected buildings, situated on flat terrain with homogeneous soil conditions.It determined the approximate number of defeats the object in a year.
depending on the category of a lightning protection system and the expected number of lightning is determined by the type of protection zone, calculated the distance between the taken pairwise lightning rods and calculated parameters of protection zones in thecertain height from the ground.
To assess the thunderstorm activity in different parts of the country use map of the distribution of the average number of hours per year storm, which are lines of equal length and thunderstorms to local meteorological station.Design of lightning protection is also carried out depending on the size of the object.
What is the lightning protection system?↑
At the heart of the development of the lightning protection system to be the principle of changing the trajectory of lightning.It requires no complicated devices to take a lightning strike from the roof, sending it into the ground along the wall.Of the existing standards should be that lightning protection of buildings is a set of activities related to the prevention of the negative effects of lightning.
to similar consequences include: the occurrence of fires, mechanical failure, loss of people current, the output of electrical equipment failure.To protect buildings and structures from lightning run an external lightning protection system.Using connecting elements of stainless steel, copper and brass can be arranged lightning protection device of buildings in different combinations and embodiments.
entire system consists of a collector, molnieprimnika and earthing.Lightning takes the first rank.Then, using the current collector assigned to the earth ground, are called to extinguish it in the ground.
Lightning for the most dangerous zones ↑
protection of buildings from lightning is made by means of lightning.Such a device lightning rises above the protected object, which is given by the lightning current into the ground, bypassing the protected object.
protective effect of lightning is based on the ability of lightning strikes the highest object, which have a solid relationship with the land.On the Lightning during the stage leading to the lightning discharge accumulated charges that create the largest electric field between the tip and the collector grounded developing leading channel of lightning.In this way and formed rank.
securable object that is lower than the air terminal, being located under or near it, is screened and therefore not struck by lightning.The space around the lightning rod system, which is protected by an electrical discharge, called area of protection.
Molniepriemnoe device protects mainly those parts of the building that are most at risk of stroke.This applies skates, edges, edges and corners of the roof structures and elements that protrude above the roof - antenna chimneys.Protects the building must be entirely within the lightning protection zone.Since the discharge path quite fickle, secure structure is provided only with a certain degree of reliability, which is not more than 98%.
susceptor, earthing and their functions ↑
a bridge between the ground and the air terminal performs collector.In order to decrease the probability of dangerous sparking Current taps are placed in such a way that between the earth and the destruction current point spread along parallel paths in length be limited to a minimum.One air terminal must move away at least two of the collector, which are made of different metal conductors - copper, galvanized steel, aluminum, and laid on inaccessible to touch places.
third link lightning protection system acts as earthing, which is designed to protect people from high contact voltage and electric current of lightning.This system combines a grounding conductors and ground wires, which are connected to a closed circuit.Calculation of lightning involves choosing the type of grounding: patchy grounding, grounding contour around the buildings, deep grounding, depth and contour to the ground releases molniepriemnoy part under Current taps.Normally, earthing switch placed in the ground to a depth of 1-2 meters.Choosing earthing, attention should be stopped on a piece of metal pipe or steel plate.
Selection lightning protection system ↑
of protection is determined on the basis of such parameters of the building: the height of the building, such as roofs, architectural construction, roofing materials.Lightning metal roofing is usually carried out on the classic version of Thunder discharge protection that has been set out above.The collector for safety better to lay on the opposite entrance wall and earthing should be placed away from buildings and foundations.
for slate and wood will require a completely different lightning protection system.With two wooden props metal cable laid along the roof ridge along the perimeter of the roof.By Lightning soldered one end of the collector, and the other goes down along the wall from the roof to a sheet of steel that serve as earthing.The collector can also be passed through the drain.From the entrance of such a system shall be located at least three meters.
Following the advice of professionals, installation of lightning protection for buildings covered with tiles, it is recommended to perform a special steel mesh wire that has a diameter of about 6 millimeters.Step cells 6 must be equal to 6 meters.The collector is soldered directly to the grid, and then descends to earth ground - bury a steel plate.A method for protecting buildings with the help of a Faraday cage is used in relation to the small rural buildings, a modern brick and reinforced concrete cottage that has a roof made of galvanized iron, which is going to the roof seam.
Thus, the lightning of buildings provides such benefits:
- protection from thunder discharge without disturbing the architectural integrity and individuality of the buildings;
- use in residential and industrial buildings at any stage;
- minimum term of this project;
- anti-corrosion properties of the material used for its production, which ensures a long useful life;
- speed protection of all types of information and network security, as well as consumers.